A typical power cutter comprises a housing in which is mounted a two stroke internal combustion engine. Attached to the side of the housing is a support arm which extends forward of the housing. Rotatably mounted on the end of the support arm is a cutting blade, usually in the form of a grinding disk. The motor is drivingly connected to the cutting blade via a drive belt. The rotary output of the engine rotatingly drives the cutting blade via the drive belt. The drive belt is driven via a centrifugal clutch which enables the out drive spindle of the engine to disengage from the belt when the engine is running at a slow speed, to allow the engine to continue running, whilst disengaging any drive to the cutting blade to allow the blade to be stationary.
Also mounted in the housing is a petrol tank which provides petrol for the engine and an oil tank, which provides lubricating oil to mix with the petrol, to lubricate the engine, to provide a petrol/oil mixture. The petrol and oil mixture is fed into the engine via a carburetor, also mounted within the housing, which creates an aerated petrol/oil mixture, to power the engine.
Mounted on the rear of the housing is a rear handle for supporting the power cutter, which contains a trigger switch for accelerating the engine upon depressing. Depression of the trigger switch causes more of the aerated petrol/oil mixture to be injected into the engine from the carburetor which in turn causes the speed of the engine to accelerate.
GB2232913, WO2005/056225 and U.S. Pat. No. 5,177,871 show such power cutters.